John askwith



M/w/Ses Z1/Mw@ Y'ATENTED MAR. s, 1867.

J. ASKWITH.

PISTON PACKING.

ma Nonms PETERS co, PHOTO-ums.. wsnmamN. n. c.

cr C? JOHN ASKWITl-I, OF CHICAGO, ILLINOIS.-

Zietters Palmit No. 62,5%, crrtud March 5,- 1867.

IMPROVEMENT IN PISTON PACKING.

dilge dnhtle referrer tu in tigen Miers @atentan making parini the sume.

'IO ALL WHOM I'l MAY CONCERN-z Be it known that I, JOHN ASKWITH, of Chicago, in the county of Cook, and Stnte'of Illinois, have invented a new and useful Improvement in Piston Packing; and I (lo hereby declare that the following is a full, clear, and exact description thereof, which will enable others' skilled in the nrt to make and use the seme, reference being had to Vthe accompanying drawings, forming pnrtof this specication.

This invention relates to the steam engine, and to a. method of preventing the steam from escaping past the piston; and the invention consists in the provision made for keeping the ring expanded to the cylinder steamtight `and in a central position.

Figure 1 represents a. horizonte-l section of the piston, showing the spider and the packing ring, and. also the method of expanding it.

Figure 2 shows en edge view of the ring in its plane, with a portion broken away to show the set-screw as it acts upon the ring to expand it or-move it.

Figures 3, 4, 5, and@ represent modifications of the `joint in the pecking ring, or the different ways in which the ring may be divided` and the joint formed.

Similar letters of reference indicate like parts.

The piston here represented in fig. 2 iseomposed of but one ring between the disk-plate or spider of the piston and the follower, but any desired number of rings may be used and operated in the same'manner.

A represents the disk or bottom plete of the piston. Bris the follower. C represents the peeking ring. D isthe piston rod. The packing ring is turned of proper size or diameter, and divided in one or moreV places, or eut across o r through the section. Each end of the ring thus made is then slotted out or rebeted, as shown in modification, iig. 6. The inner side of each of the ends so relmted, is recessed or cut away, Ves seen in' iig. 1* E is a. piece fitted into the recesses and the rebutment thus formed. The tongue portion is iush with he periphery' of the ring, and the edges back of the tongue are flush with the upper and the lower side of the ring. The inner side hns ratchet teeth, which receive the end of a. spring,f, which spring beurs against it, and keeps it in place and the ring expended. Cris a. flange upon the plete A, through which the set-screws h work for the purpose of keeping the ring in a. cent1-ail position, and expanding it when it becomes worn or loose. The ring is not made to fit tight between the plate A and the follower B. A little steam is allowed to enter the recess or centre of the piston, and to press out the packing ring when the engine is running. There ere small holes through the iiange G toassist in this operation.

I do not eontine myself to the particular form of joint described above; either of the modifications shown may be used, with the same or a. similar etfect, and any number ofjoints may be used; but having thus described my invention, what I claim as nemend desire to secure by Letters Patent, is-

The ratchet-piece E, the spring f, and the set-screws h, in combination with the ring C, as and for the purpose set forth:

JOHN ASKWITH.

Witnesses:

FRANKLIN GHAVETT. A. D. HUNTER. 

